The unusually cool and wet pattern which gripped the
Northeast in June continued in July with the prevailing polar branch of the jet stream
displaced far to the south across the northern third of the United States. A semi
permanent area of low pressure continued over the Hudson Bay region of Canada. The
Canadian upper low, more common in the winter and early spring months, than during the
summer, spun down an unusually strong and southward tracking upper level storm offshoot
which when it interacted with the normally high summer moisture levels in the atmosphere,
produced an excessive rain event for eastern New York and western New England during the
July 14-16th period. This was the second warm season excessive rain event of the
year following the anomalous early June Nor'easter.

Friday, July 14

The initial phase of the
storm began as the intensifying early spring type upper low pushed south out of Canada on
a track for western New York. Typical warm and humid weather prevailed over eastern
New York and western New England with temperatures in the low 80's and dewpoints in the
mid 60's. Scattered clusters of T-storms developed as a result of the upper
atmosphere cooling, in direct response to the approach of the upper low. Daytime
heating of elevated terrain, was sufficient to start thermals which became heavy rain
making t-storms in Ulster county and in Fulton, Montgomery, Herkimer and southern Hamilton
counties. The steering flow on the 14th was quite weak, common in July, so once the
t-storms formed they remained nearly stationary over generally the same isolated
areas. Rainfall amounts estimated by Doppler radar in parts of central Ulster county
in and near the Ashokan reservoir approached a whopping ten inches, with a WeatherNet 6
measurement of 6.68" in West Shokan. Similarly, rainfall amounts between two
and seven inches occurred in small parts of Herkimer, Fulton, and Montgomery
counties. Localized flooding occurred as a result of the heavy rain. This
heavy rain, however, was very isolated in nature, when compared to the remaining area,
which had little or no rain.

Saturday: July 15

The widespread rain event
developed during the early morning on Saturday, July 14, when the upper low, which had now
become quite strong containing very cold air aloft, eased south into western New York and
then stalled. The upper storm initiated a weak and strung out area of low pressure
at the surface from near Buffalo, NY to Wilmington, NC. Simultaneously, high
pressure, on the 15th, was located over the north Atlantic. The combined flow, both
at the surface and aloft, between the weak surface lows and the strong high to the east
was from the southeast off the moisture rich Atlantic ocean. The flow provided an
almost unlimited supply of moist air, which when forced to rise, due to atmospheric
instability caused by the cold air aloft and diffluent flow, produced record rains in the
Capital Region. 3.23" of rain fell on the 15th at Albany, setting a twenty four
hour rainfall record. The fact that the parent upper low stalled out much of
Saturday and Saturday night meant that no weather features moved for almost 16 hours
resulting in the continuous, semi-stationary feed of moisture. The band of steady
moderate to heavy rain was relatively narrow extending from south of Long Island north to
the Capital Region and then arced back into the Mohawk valley and the Adirondacks. Steady
rain fell in this zone from the early morning until close to midnight. Rain became
extremely heavy, from 6pm to midnight on the 15th. In that six hour time frame two
to four inches of rain fell, combined with the one to two inches of rain that had fallen
in the previous six hours, to produce widespread urban, creek, small river, and stream
flooding over a wide area from the eastern Catskills to the mid Hudson valley, Berkshire
and Litchfield counties in MA and CT respectively, the Capital District and the Mohawk
valley. The following is a listing of some, but not all, of the reported flooding in the
area.

1:50pm: Olivebrige, Ulster County:

Flooding, Route 101 impassable

7:25pm: New Milford, CT, Litchfield County:

Aspatuck River out of its banks

7:50pm: Colonie, Albany County:

Street flooding, Sand Creek Road closed

7:50pm: Sheffield, Berkshire County, MA:

Route 40 closed due to flooding

7:55pm: Great Barrington, MA:

Many road closed due to flooding and backed up sewers

8:15pm: East Schodack, Rensselaer County:

Road closed due to flooding

8:30pm: Latham, Albany County:

Route 9 closed due to flooding

9:40pm: Nassau, Rensselaer County:

Roads closed due to flooding

10:05pm: Chatham, Columbia County:

Many roads closed and people evacuated due to flooding

10:35pm: Albany, Albany, County:

Central Avenue closed due to flooding

Sunday, July 16

The main area of upper
level low pressure through the 16th drifted south into Pennsylvania and weakened. As
a consequence of the storm's weakening and shift in position south, the surface low also
weakened and therefore the strong, moisture rich Atlantic inflow into the Northeast broke
down through the early morning hours of the 16th which brought an end to the continuous
rain. Very humid air, however, remained in place over the region with dewpoint
temperatures in the mid 60's. Intervals of sunshine developed across much of the
area which was a nice psychological boost to folks, having been shut in the day before.
The atmosphere, however, aloft remained cold, so with the advent of sunshine, and
surface heating, especially of the elevated terrain, scattered showers and t-storms
developed, much as they had done on Friday as the parent upper storm was making its
approach. Rains on the 16th were scattered, but once again torrential where they
occurred due to a very weak steering flow. Like the 14th, t-storms developed over
the mountains, and remained almost stationary producing between two and seven inches of
additional rainfall in parts of Washington county, eastern Rensselaer and Columbia
counties in NY, and Bennington county, VT. In fact in Bennington county, VT, four to
seven inches of rain fell in three hours along route 7 between Shaftsbury and Bennington.
Severe flash flooding occurred throughout southern Bennington county as a result of
this additional rainfall on the 16th. By midnight, most of the stationary t-storms in the
hills east of Albany had ended concluding this storm event. The following is a
listing of some, but not all of the flooding produced by these t-storms.

The following table lists a number of rainfall measurements
from the 14th through the 16th from the National Weather Service Cooperative observers
network as well as the Channel 6 WeatherNet 6 weather watcher network.